Preparation of chemically sintered ZnO films and their application in dye sensitized solar cells formed on plastic substrates

Meso-porous zinc oxide films were prepared on tin-doped indium oxide-coated, polyethelene naphthalate substrates from binder-free ZnO slurry. The reaction with ammonium hydroxide was found to increase connection between ZnO grains by forming a nano-rod like structure followed by heating at 150 °C. The enhancement of adhesion among ZnO grains was evaluated using a nano-scratch technique. Two different xanthene dyes were used to sensitize ZnO electrodes, with a photo-voltage of 657 mV, fill-factor of 73% and photo-current of 4.1 mA cm−2 with a maximum light to-electrical energy conversion efficiency of 2.0% being obtained for the plastic based ZnO|mercurochrome|electrolyte solar cell under 1 sun.